Last week at internal Citrix Sales Engineer gathering, I was presenting stuff on Application Streaming, where I noted that Application Streaming cannot isolate 16-bit DOS applications. Immediate response from the SEs, yes it does - I have it in production and it works. … Things that make you go hum.
I went home and tested it. Answer: The SEs are completely right.
Why? Our file system driver is kernel mode and “sees all”. Same for the code that looks after processes coming and going. There would be a problem with registry filtering and this would be a show stopper, except there is no registry for DOS apps. So, I’ve been telling people for years that this is a product limitation, when it really isn’t.
Here’s a picture of Turbo Pascal, 1987 vintage, running under Citrix Application streaming. Also note that I saved Hello.pas to the C:\Turbo directory, which shows up in per-user layer of isolation.